Study Of Vane Welding Temperature Field Measurement System Based On Color CCD

The temperature measurement plays an important role in the process of steam turbine vane welding, because the welding temperature is a pivotal parameter to insure the quality of production, achieve the autocontrol and optimize the decision-making. However, it is difficult to achieve the real time measurement of welding temperature field by the existing high temperature measurement techniques because of the complex techniques and the bad condition in the welding process. Therefore it is urgently necessary to develop a simple and convenient temperature measure device which is capable to measure the temperature field of welding steam turbine vane quickly.Recently, with the development of photoelectric technology, computer technology and digital image processing technology, the contactless temperature measurement technology based on color CCD sensor has become a focus of research in the field of high temperature measurement. The paper based on the hot radicalization theory and the color CCD imaging theory, study the measuring method of temperature field. Discuss the relations between the color CCD output signal and the temperature of radiator in detail. Aiming at the problem that the level of temperature measurement veracity is low, the paper analyses the main sources of the measure error and calibration method about colorimetric temperature measurement. All the essential equipment structuring of the contactless temperature measurement system are studied, before the method how to select temperature measurement equipment is proposed, design contactless temperature measurement system based on color CCD image sensor. The method how to avoid such negative influence is discussed in view of that some functions of CCD camera bring some negative influence to temperature measurement. Using LabVIEW as a tool to program an applied software called"Weld Temperature Detecting System"based on the state machine design model, the software has the following features: Firstly, it can display the temperature field with pseudocolor and histogram in the way of temperature distribution; Secondly, the temperature of arbitrary point selected by mouse can be showed; thirdly, it can alarm when the temperature is unnormal.